How Much Are Sea Otters Worth on the Carbon Market?

Baby puffins starving off the coast of Maine because herring have moved to colder waters, sea turtles in Brazil hatching mostly females because of warmer sands — there’s no question that climate change threatens the continued existence of thousands of species, including that forlorn-looking polar bear on his shrinking iceberg.

Off the coast of the Aleutian Islands, for example, researchers at the University of Santa Cruz have found that sea otters essentially control one of the ocean’s largest carbon sinks — kelp forests. That’s because sea otters are the main predators of sea urchins, which, if released from the pressure of predation, quickly multiply and decimate kelp forests down to bare ocean floor. While a lot of sea otters are best for keeping urchins at bay, even a few sea otters can help limit the damage to the kelp by forcing urchins to spend most of their time hiding amongst the rocks instead of brazenly marching across the kelp beds eating everything in sight.

Kelp beds protected by otters absorb 12 times more carbon dioxide than those thinned out by urchins, according to the research.

Around the world, ecosystems which keep carbon dioxide locked up and out of the atmosphere are getting more and more attention. Until recently, Ecuador was successfully raising funds from other nations to keep Ecuadorian forests intact, and the massive amounts of carbon they hold, in the ground. Likewise, the United Nation’s REDD program — Reducing Emissions from Deforestation and Forest Degradation — is devoted to finding economic mechanisms to help incentivize developing countries to protect their carbon rich forests. Despite all this, however, very little attention is given to the role of animals in the carbon cycle.

The researchers at UCSC used the current price of carbon on the European carbon market to estimate the value of sea otters in their study site in terms of the quantity of kelp that the otters protect. They found the carbon sequestered by the living kelp was worth somewhere between $205-$400 million.

While current carbon markets clearly aren’t evolved enough to pay for otter conservation, the hope is that one day there will be structures available to place the appropriate value on sea otters, which, at present, not only give us their cuteness for free, but also their services as guardians of the rain forests of the deep.